RISK-FACTORS FOR TRYPANOSOMA-CRUZI INFECTION IN CALIFORNIA BLOOD-DONORS

Background: Trypanosoma cruzi, the protozoan parasite that causes Chag as' disease, is endemic in Central and South America and in Mexico. Ri sk of infection is related to exposure to insects harboring T. cruzi o r to the transfusion of blood from an infected donor Large numbers of immigrants from endemic areas reside in California, but the frequency with which persons at risk for T. cruzi contribute to the blood supply there is not known. Study Design and Methods: A questionnaire was use d to survey donors in 18 California donor centers for risk factors for T. cruzi infection. Results: Otherwise eligible allogeneic blood dono rs (n = 17,521) completed questionnaires, Of this group, 427 (2.4%) ha d lived in endemic areas for more than 1 year, and 39 of these donors had lived in dwellings with mud walls or thatched roofs. Sixteen donor s had received transfusions in endemic areas, Six donors gave a histor y of Chagas' disease. Fifty-seven donors (0.33% of total) had at least one risk factor for T. cruzi infection. Donors at risk for T. cruzi w ere found in all 18 centers studied, at a median prevalence of 1 per 3 40 donors, Conclusion: Donors at risk for T. cruzi are contributing to the blood supply throughout California, Further consideration should be given to donor screening for this transfusion-transmissible infecti on.